Java by huanghengdong


									Feb 24: Desinging to Fit Human Capabilities;
Psychological Aspects; Participatory Design

 Guest lecture: Dan Comden, UW DO-IT Program
  (Disabilities, Opportunities, Internetworking, and
 Administrivia
     early turn in of introduction and methods section now optional
 Topics for tonight
     Participatory Design
     Various topics in cognitive and social psychology as they relate
      to HCI
          Discussion of assigned papers
          “Computers as Social Actors”
          Role of metaphor

CSE 595, Winter 2000                                                     1
Universal Design for the Web

Dan Comden
Adaptive Technology Lab
DO-IT Program
University of Washington
Web Overview
     clickable text regions
     location of information isn’t important

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Evolution of the Web


SGML - Standard Generalized Markup

HTML - Hypertext Markup Language

XML - Extensible Markup Language

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Current Utilization

Commercial Sites



Personal “brag” pages

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Why Universal Design?

Equality of access to information


Commercial Implications

Examples from architecture

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What Affects Accessibility?
     not everyone uses IE or Netscape
Connection speed
Personal preference
Visitor knowledge level
Language proficiency

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What Affects Accessibility?
Visitors with Disabilities such as:
Visual impairments
Hearing problems
Mobility difficulties
Learning Disabilities

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Adaptive Technology Video
Tips and Tricks
Consistent Interface
Stick to HTML specs
Test with more than one browser
Provide alternate text for images/video
Avoid frames
Don’t use client side image maps
High contrast color

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Consistent Layout

Provides a recognizable method of navigation

Attempt consistency through domain

Benefits: Everyone, particularly those with
   mobility and learning impairments

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HTML Specifications

Universally recognized tags
     Unlike <BLINK>

Benefits: Anyone using text-based or non-
   standard browsers

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Animation anyone?
“It is rare to see a web animation that has any
 goal besides annoying the user.“
     Jakob Nielsen Alertbox, January, 1999

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Test your pages!

Use a variety of browsers
     At least one text-based browser
     SSL won’t work with Lynx

Benefits: All potential visitors.
Server detection of web browser or text-only
 versions mean more work!

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Provide alternate text
Not everyone can see images
     Visitors with visual impairments
     Browsers with images turned off

<ALT> attribute is a great tool

Benefits: anyone who can’t see graphics

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PDF files
Convert simple PDF to HTML or ASCII
Works poorly with complex PDF files
Source cannot be an image
Not a general purpose conversion tool

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Streaming Audio/Video
Open captioning is easiest
Tools for captioning existing files:
     W3C’s Synchronized Multimedia Integration
      Language (SMIL)
     Microsoft’s Synchronized Accessible Media
      Interchange (SAMI)
Text version should be included, with

CSE 595, Winter 2000                              17
Streaming Audio/Video

Java Accessibility
Java 2 has accessibility built-in to JFC

Java Accessibility Utilities offer extended
 services for JDK 1.2

IBM offers detailed guidelines linked from Sun’s

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Single Design Pages
Some contradictory ideas:
Different versions for different users?
     Too much extra work
     often out of date
Different versions for different clients?
     screen sizes (handheld vs. desktop)

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Cascading Style Sheets
Easy maintenance
Helps consistency
Can rarely be overridden by individual designer!
Ultimately decided by viewer

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 Frames: Usability Snafu?

   Change frameset with TARGET =“_top” attribute
Does print model make sense?
Screen real estate
Search engine problems

May be appropriate for intranet

 CSE 595, Winter 2000                               22
Future of the Web
New directions
     browser-specific (IE vs. Netscape vs.. ?)
     handheld/other clients
HTML updates
A return to consistent, clean presentation
 of information?

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Universal Design <> Boring

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Fix home and high traffic pages first

W3C’s priority guidelines

Usability testing

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Do’s and Don’ts
 DO:                            DON’T:
     use text                    client side ISMAPS
     consistent interface        Frames
     <ALT> text                  omit <ALT> text
     usability testing           browser-specific features
     caption & transcribe        Difficult backgrounds
     accessibility statement     use “click here”
     descriptive links

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   DO-IT                          
   W3C Accessibility Initiative   
   PDF access                     
   Java access                    
   Trace R&D Center               
   Nielsen’s            
   Web Pages That Suck            
   WGBH/NCAM                      
   Webwatch email list            

     CSE 595, Winter 2000                                           27
Questions & Comments
Papers for This Week with Reviews
 Cooperative Design: Techniques and Experiences from
  the Scandanavian Scene
     Average rating: 4.5 (range 2-6)
 The Diversity of Usability Practices
     Average rating: 4.4 (range 3-5)
 Internet Paradox: A Social Technology that Reduces
  Social Involvement and Psychological Well-Being?
     Average rating: 4.7 (range 2-6)
     a lively set of reviews:
          “This is a great article not because I agree with it, but because I
           think such studies are incredibly dangerous.” (student A)
          “Thanks for requiring us to read this paper. I’m going to distribute
           references to it to everyone I work with.” (student B)

CSE 595, Winter 2000                                                         29
Other papers (no reviews)
 Human Information Processing
     User Technology: from Pointing to Pondering
     The Growth of Cognitive Modeling in Human-Computer
      Interaction Since GOMS
     The Contributions of Applied Psychology to the Study of Human-
      Computer Interaction
     Let’s Get Real: A Position Paper on the Role of Cognitive
      Psychology in the Design of Humanly Useful and Usable
 Error
     Human Error and the Design of Computer Systems
     Human Error and the Search for Blame
     Designing for Error

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GOMS Model
 A (low level) representation of a user’s cognitive
     operators (actions belonging to a user’s repertoire of skills)
     methods (sequences of subgoals and operators often carried out
      in an automatic fashion to achieve goals)
     selection rules (for choosing among different possible methods
      for reaching a particular goal)
 predicts the methods that a skilled person will employ to
  carry out editing tasks and the time they will take
 various levels — keystroke level most heavily studied
 some applications: text editing, video games, telephone
CSE 595, Winter 2000                                              31
The Role of Cognitive Psychology
in HCI
contrasting positions:
     Phil Barnard, “The Contributions of Applied Cognitive
     Thomas Landauer, “Let’s Get Real: A Position Paper
      on the Role of Cognitive Psychology in the Design of
      Humanly Useful and Usable Systems”

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Participatory Design
reading: “Cooperative Design: Techniques and
 Experiences from the Scandanavian Scene”
Other resources:
     Proceedings of biennial Participatory Design
     G. Bjerknes, P. Ehn and M. Kyng, “Computers and
      A Scandanavian Challenge”
     J. Greenbaum and M. Kyng, “Design at Work:
      Comparative Design of Computer Systems”

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Participatory Design — Original
Scandanavian co-determination laws —
 workplace democracy
strong trade unions
in-house or specialized systems —
 not mass-market shrinkwrap software
long tradition and current practice in
 Scandanavia of related ideas, e.g. Citizen’s
 Panels in Denmark on controversial new

CSE 595, Winter 2000                            34
Participatory Design — Some
 Computer systems that are created for the workplace should be
  designed with full participation from the users.
 Computer applications should enhance workplace skills rather than
  degrade them.
 Computer applications should be viewed as tools, under the control
  of people using them.
 Introducing computer applications changes the organization of
  work. The use situation is a fundamental starting point for the
  design process.
 Computer applications should be looked at as a means of increasing
  quality of results, not just quantity.
 The design process is a political one and includes conflicts at almost
  every step. These conflicts should be addressed, not ignored or
  pushed aside.

CSE 595, Winter 2000                                                  35
Participatory Design — Tools
workplace visits with interviews and
future workshops
     critique phase
     fantasy phase
cooperative prototyping; rapid feedback
more recently: ethnography

(Aside: note the influence on Contextual Design)
CSE 595, Winter 2000                               36
Participatory Design — Theoretical
analytic tradition vs. social construction
philosophical foundations:
     Ludwig Wittgenstein (Philosophical Investigations,
      not the Tractatus Logic-Philosophicus) — in particular
      Wittgenstein’s notion of language games
     Martin Heiddegger
     Karl Marx

CSE 595, Winter 2000                                      37
Quote of the Week
“Well, I don’t really know how to tell you what I don’t like about the
  system. I guess one of the things is that it makes me think and
  work differently, like for example, when I want to make separate
  columns, I need to type it and then rearrange it. That’s not the
  way I see it in my mind.”
     -- Word processing user, quoted at the beginning of the chapter
  “Introduction: Situated Design” in Design at Work: Cooperative
  Design of Computer Systems by Joan Greenbaum and Morten Kyng

“If a lion could speak, we could not understand him.”
    -- Ludwig Wittgenstein, Philosophical Investigations

CSE 595, Winter 2000                                                 38
“The Diversity of Usability
special section of May 1999 Communications of
 the ACM
juxtaposition of Danish and U.S. companies
interesting to note: influence of participatory
 design and information user involvement in the
 current practices of the Danish companies

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“Internet Paradox”
HomeNet study:
     longitudinal study — first 1 to 2 years online
     sample of 93 Pittsburgh families
     8 diverse neighborhoods
     Year 1 sample drawn from families with teenagers in
      high school journalism classes
     Year 2 sample drawn from families with an adult on
      a Board of Directors of a community development

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from yesterday’s Seattle PI

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Joseph McGrath, “Methodology

     “… it is not appropriate to ask whether any given study is flawless,
       and therefore to be believed (as in the query, ‘but is that study
       valid?’). Rather we should ask whether the evidence from any
       given study is consistent with other evidence on the same
       problem, done by the same or other researchers using other
       strategies and other methods. If two sets of evidence based on
       different methods are consistent, both of those sets of evidence
       gain in credibility. If they are not consistent, that inconsistency
       raises doubts about the credibility of both sets. … The
       fundamental principle in behavioral and social science is that
        credible empirical knowledge requires consistency or
        convergence of evidence across studies based on multiple

CSE 595, Winter 2000                                                    42
“Internet Paradox” — Findings
inferred a causal connection between increased
 internet use, decreased social involvement, and
 increased depression.
     not a large effect
     not a representative sample of people (the
      participants already had various other social
      connections, lived in a large city, included few
      disabled people, etc.)

CSE 595, Winter 2000                                     43
“Internet Paradox” — Design
Any design implications are speculative at this
     small sample, preliminary results
     Internet and computer technology changing rapidly
suggestions from the CACM paper:
     technologies such as Buddy Lists in AOL Instant
      Messenger, HP’s Message Board may make Internet
      use more beneficial in the home
     lower connection latencies
     make internet use more social (for example, multiple
      keyboards, applications that encourage use by
      several people)
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Social Capital
 related phenomenon (cited in paper) - decline in “social
 reference: Robert Putnam, “Bowling Alone: America’s
  Declining Social Capital”, Journal of Democracy Vol 6
 Trends in the U.S. over the last 35 years: Citizens
     vote less
     go to church less
     discuss government with their neighbors less
     are members of fewer voluntary organizations
     have fewer dinner parties
     generally get together less for civic and social purposes

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Social Capital (2)
the cause …??
Putnam blames television
Some controversy — see e.g. Nicholas Lemann,
 “Kicking in Groups”, Atlantic Monthly, April 1996
     “Just as intriguing as Robert Putnam’s theory that we
      are ‘bowling alone’ — that the bonds of civic
      association are dissolving — is how readily the theory
      has been accepted.”

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“Computers are Social Actors”
 optional paper by Clifford Nass, Jonathan Steuer, and
  Ellen Tauber, CHI 94

   Material here also taken from:
     “Computers Are Social Actors: A Review of Current Research” by
      Clifford Nass, Youngme Moon, John Morkes, Eun-Young Kim,
      and B. J. Fogg, in Batya Friedman, “Human Values and the
      Design of Computer Technology”
     a lecture by Clifford Nass at NSF HCI Grantees Workshop,
      August 1997

CSE 595, Winter 2000                                              47
Do People Respond Socially To
Folk wisdom:
     Of course. We mutter at the washing machine,
      swear at the computer, talk back to the telephone
      (just the bell part, I mean).

Traditional academic response (according to
     it's an aberration (lack of knowledge, or
      psychological or social dysfunction)
     social behavior is directed at the human creator of
      the program or machine
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Nass’s Experimental Approach
Pick a social science finding (theory and
 method) concerning behavior or attitude toward
 other humans.
Change “human” to “computer” in the
 statement of the theory.
Replace one or more humans with computers in
 the method of the study.
Provide the computer with some human
 characteristics (language output, voice, etc)
Determine if the social rule still applies.
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Some Social Behaviors
politeness norms
response to personality types
gender stereotypes
team affiliation

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The Subjects

Stanford undergraduates in communications
 classes (in published paper)

Stanford computer science graduate students
 (mentioned in Nass’s lecture)

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Politeness Norms
Tutoring, testing, evaluation task. Following
 task completion, subject interviewed about the
 performance of the computer.
     1. interview conducted by same computer
     2. interview conducted using pencil and paper
     3. interview conducted by an idential computer in
       another room
Responses were significantly more positive and
 more homogeneous for condition 1.

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Politeness Norms (2)
These were all simple text-based interfaces.
In post tests, all the subjects said (sometimes
 vehemently) that it would be absurd to engage
 in polite behavior toward a computer.

Another set of experiments: voice output, using
 same voice or different voice.
     Subjects rated the performance more positively for
      the same-voice condition.

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Design Implications
(according to Nass)
 Product evaluation questions should not be asked by
  product itself.
     Nor should they be asked by the technology used to test the
      product (despite convenience).
     Use pencil and paper, or a different technology.
 Users may expect politeness from computers. Most
  systems avoid direct insults, but for example error
  messages are often impolite.
 Cultural issues: internationalization may require more
  than just translating the interface text.
 Aside: results of usability studies conducted by the
   software developer are suspect!
CSE 595, Winter 2000                                                54
Attraction and Personality
 Social psychology: one of the best predictors of whether
  two people will like each other is to find how similar
  they are.
 Personality trait tested: dominance/submissiveness
 Personality programmed using very simple
  preprogrammed text-based cues.
 Example from Desert Survival Task tutoring program:
     “You should definitely rate the flashlight higher. It is your only
      night signalling device.”
     “Perhaps the flashlight should be rated higher? It may be your
      only reliable night signalling device.”

CSE 595, Winter 2000                                                   55
Attraction and Personality: Results
Users identified dominance and submissiveness
 in the programs.
Users were able to detect similarity of the
 computer's personality to their own.
There was strong evidence that subjects
 preferred interacting with computers that
 shared their personality type. (This was
 consistently true for all personality types.)

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 “People are phenomenal suckers for flattery.’”
 Experiment: a guessing game. Test conditions:
     generic feedback (“Begin next round.”)
     sincere praise (“Great job! You seem to have an uncommon
      ability to structure data logically.”)
     flattery (same, but subjects told that evaluation portion of
      program not yet written, and computer feedback had nothing to
      do with their performance)
 Result: subjects in both sincere praise and flattery
  conditions felt much more positive about themselves
  and the computer.
 No significant difference between sincere praise and
CSE 595, Winter 2000                                             57
Flattery: Design Implications
Most current computer applications are heavily
 geared toward critical feedback.
Add positive feedback? Even noncontingent
Categories of software for which this might be
     training and tutorial software
     software that enhance user creativity
     software for performing unpleasant tasks
(Aside: should we be doing this, even if it
CSE 595, Winter 2000                              58
Gender Differences
Stereotypes tested:

dominant behavior by men vs. women
evaluation coming from men vs. women
knowledge about various topics
     experiment: knowledge about computers and
      technology, knowledge about love and relationships

CSE 595, Winter 2000                                       59
Gender Differences: Results
 Female-voiced computer in a dominant role was
  evaluated more negatively than a male-voiced computer
  in the same role. It was perceived as significantly less
  friendly. This was true for both female and male
 Evaluations from a male-voiced computer was regarded
  as significantly more “competent” than from a female-
  voiced computer. This again was true for both female
  and male subjects.
 The female-voiced computer was perceived as a better
  teacher on the subject of love and relationships; the
  male-voiced computer was perceived as better for
  computers and technology.
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Gender Differences: Theoretical and
Design Implications
 The tendency to gender-stereotype is so deeply ingrained in human
  psychology that it extends even to computers. Vocal cues alone
  elicited this response.
 Choice of gender of a computer's voice is an important design
  decision. Choosing a male voice or a female voice cannot be a
  neutral decision.
 Computer voices may indicate much more than gender — for
  example, age, social class, geographic location. This may create
  expectations about how the computer will behave.
 Example: what voice should be chosen for a CD-ROM with medical
  advice for pregnant women? Male or female? How old should it
  sound? Accent? Two or more voices?
 Should computer agents conform to stereotypes at all? Should we
  design agents that challenge stereotypes? (Example: synthetic
  gender-neutral voice.)
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An Alternative Explanation?
 Is the social behavior directed at the human creator of
  the program or machine?
 Social psychology predicts no — people orient toward
  proximate sources (“blame the messenger”).
 Experiment: half of subjects told they were working with
  computers, half told they were working with
 Result: subjects who were told they were working with
  computers perceived the tutor to be significantly more
  friendly, effective, playful, and similar to themselves.
 If social behavior were directed at the programmer
  rather than the program, there should have been no
CSE 595, Winter 2000                                    62
Implications for Agent Research

 Maes: “The agents have deliberately all been drawn as
  simple cartoon faces, in order not to encourage
  unwaranted attribution of human-level intelligence.”
 Nass: “Furthermore, these studies suggest that it does
  not take extremely sophisticated technology to generate
  social responses.”

 But: see the Maes/Shneiderman debate (in next week’s
  optional readings)

CSE 595, Winter 2000                                    63
Metaphor in User Interface Design
 Folk wisdom: outside of the computer domain, metaphor
  is restricted to poetry and flowery writing.
 Within the computer domain, for user interfaces the
  desktop metaphor is well-known, and other kinds of
  graphical user interfaces are often consciously designed
  with a metaphor in mind (see e.g. Thomas Erickson's
  chapter "Working with Interface Metaphors").
 However, we don't usually talk about other kinds of
  interfaces, e.g. textual ones, as being constructed based
  on a conscious metaphor, nor do we often talk about
  the metaphors behind other aspects of computers.

CSE 595, Winter 2000                                     64
“Metaphors We Live By” by
George Lakoff and Mark Johnson
 Lakoff and Johnson argue that metaphors are not just
  restricted to poetry, flowery writing, and Macintoshes,
  but an essential part of everyday speech, and indeed
  our conceptual system.
 Particularly if they are correct, the study of metaphor
  becomes an essential part of studying human-computer
 The essence of metaphor is understanding and
  experiencing one kind of thing in terms of another.
 They further argue (based primarily on linguistic
  evidence) that most of our ordinary conceptual system
  is metaphorical in nature. Examples: “argument is war,”
  “time is money.”
CSE 595, Winter 2000                                    65
Metaphorical Systemacity

Everyday metaphors are used pervasively and
     conduit metaphor
     orientational metaphors

CSE 595, Winter 2000                           66
The Conduit Metaphor
Ideas (or meanings) are objects.
Linguistic expressions are containers.
Communication is sending.
     deliver a lecture
     Powerpoint presentation
     “Did you get that?”
     a spirited exchange of views

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Orientational Metaphors
happy is up; sad is down
conscious is up; unconscious is down
health and life are up; sickness and death are
having control or force is up; being subject to
 control or force is down
more is up; less is down
rational is up; emotional is down

CSE 595, Winter 2000                               68
Other Metaphors
Ontological metaphors (ontology: “the branch of
 metaphysics dealing with the nature of being”)
     entity and substance metaphors
     container metaphors
     example: inflation as a person
Metonymy (using one entity to refer to another
 that is related to it)

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Challenges to Coherence of
 Example: time as a moving object ... apparent
  contradiction in our metaphor for time.
   “In the weeks ahead of us …” (future is in front of
   “In the following weeks …” (future is behind us)
 However, in the first example, time is moving toward
  us; in the second, the weeks that follow are following
  the current week.
 Another example: love as a journey ... different kinds of
  journeys (car trip, train trip, sea trip). Here, there are
  various metaphors for love, but they are all coherent.

CSE 595, Winter 2000                                       70
How is Our Conceptual System
Are there any concepts that can be understood
 directly, without metaphor? If not, how can we
 understand anything at all?
prime candidates: simple spatial concepts, such
 as "up", that arise out of our direct experience
 as beings with bodies in the world.

CSE 595, Winter 2000                            71
Connecting Lakoff and Johnson
with User Interfaces
First, note that all UI's have a metaphorical
 basis, whether this was part of the designer's
 conscious thought or not.
Example: unix
            command
            file system
            link
            shell
            process (process as a person; process as a path)
            stream
            etc!
CSE 595, Winter 2000                                            72
Computer examples of Lakoff &
Johnson's metaphor lists:
Conduit metaphor:
     send data
     give it an input expression
Orientational metaphor:
     network is down
     high-level language
     low-level systems programming
     high-level design
     descend into hacking

CSE 595, Winter 2000                  73
Computer examples of using
ontological metaphors
 data as a substance (capture the data from the
 data as food (the computer ate my data; it spit out the
  data; raw data)
 data as a liquid (data flows from one place to another,
 configuration or state as an object (save your current
 Computer as vehicle: the system crashed; the processor
  is running.
 Computer as a container: input-output
 Process as a path: fork off a new process; do a join.
CSE 595, Winter 2000                                      74
the computer ate my file. It first looks at the
 characters in the input buffer, then ...
Agents. Reactive systems.
metonymy: Fred is hogging the disk drive. Sue
 is going to buy a 486.
importance of direct manipulation user
 interfaces -- they tap into early childhood
 experience and prototypical causation

CSE 595, Winter 2000                               75
Metaphor in the Alternate Reality
The Alternate Reality Kit was a system
 constructed by Randy Smith at Xerox PARC in
 the 80's. It has a very strong physical system
 metaphor. All objects have position and velocity,
 for example.
Smith notes that there can be a tension
 between literally following a physical metaphor,
 and ease of use, functionality, and performance.
 He proposes a literalism-magic distinction.

CSE 595, Winter 2000                            76
Alternate Reality Kit
 Examples of Literal/Magical distinction
   use of the hand - literal
   activation of simple buttons - literal
   manipulating buttons (dropping a button on an object) -
    moderately magical
   interactors - highly magical
   multiple realities - highly magical
 generalizing: it seems that people usually don't have
   much trouble with extending a metaphor, mixing
   metaphors, or (to a lesser extent) moving way beyond a
   metaphor. (Compare this with the notion of “coherence”
   in Lakoff & Johnson.) They really don't like things that
   fall within the metaphor and contradict it. (L&J call this
CSE“consistency” or “lack of consistency.”)
    595, Winter 2000                                          77
Thomas Erikson, "Working with
User Interface Metaphors"
 The interface to a program will have metaphors,
  whether we design it that way or not.
 Metaphor evalation:
     How much structure does the metaphor provide?
     How much of the metaphor is applicable to the problem? (Lakoff
      & Johnson call this the “used” portion of the metaphor.)
     Is the interface metaphor easy to represent?
     Is it suitable for the audience?
     Is it extensible? (Can we usefully employ the unused portion of
      the metaphor?)
     What are the metaphor's connotations? (These will depend on
      the user!)

CSE 595, Winter 2000                                               78
Metaphors for the World Wide Web
Example to be used in class discussions:
     W3 is a spider web.
     The internet is a highway system. W3 pages are
      destinations on the highway. (Compare with infobahn
     W3 is an ocean.
     The internet is outer space (cyberspace). W3 pages
      are different worlds.
     W3 is a city.
     W3 is a (very big) desktop.

CSE 595, Winter 2000                                   79

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